Of the 300 oaks known in the world, 55 are native to North
America, and most of these are in the eastern United States. The oaks make up the largest
group of forest trees native to New York. In all there are 16 species of oaks native to
this state. They grow under a wide range of conditions and show wide variations in form
and other distinguishing characteristics. The oaks of New York do not thrive in the high
forests of the mountains; therefore, representatives of the family found in the Adirondack
section are in the sheltered valleys of the foothills. South and westward in the drainages
of the Susquehanna, Genesee, and Alleghany Rivers, they become very plentiful in variety
and number.

The best way to get acquainted with New York oaks is to divide
them into two major groups, the one group to comprise the white oaks and the other the
black oaks. It is easy to place the oaks of New York in these two groups by remembering
the following characteristics of each:

The white oaks - The
leaves of the members of the white-oak group have rounded lobes (not bristle-tipped), and
the kernels of the acorns are usually sweet. All the oaks of this group mature their
acorns in a single season; for this reason they are sometimes called "annual
oaks." The most important members of the group in New York are white oak, swamp
whiteoak, bur oak, post oak, and chestnut oak.

The black oaks - The
leaves of the members of the black-oak group have bristle-tipped (not round-lobed) leaves,
and the kernels of their acorns are usually bitter. All the oaks of this group require two
seasons to mature their acorns; for this reason the representatives of this group are
sometimes called "biennial oaks," which means two-year oaks in contrast with the
one-year white oaks. The immature acorns are very helpful in recognizing the members of
the black-oak group, especially during the winter months when the trees are without
leaves. The most important members of this group in New York State are black oak, red
oak, scarlet oak, and pin oak.